IFEC   20925
INSTITUTO DE FARMACOLOGIA EXPERIMENTAL DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
Stress response recruits the hippocampal endocannabinoid system for the modulation of fear memory.
Autor/es:
LUCAS DE OLIVEIRA ALVARES, DOUGLAS SENNA ENGELKE, FELIPE DIEHL, RÓBSON SHEFFER-TEIXEIRA, JOSUÉ HAUBRICH, LINDSEY DE FREITAS CASSINI, VICTOR ALEJANDRO MOLINA AND JORGE A. QUILLFELDT
Revista:
LEARNING & MEMORY (COLD SPRING HARBOR, N.Y.)
Editorial:
COLD SPRING HARBOR LAB PRESS
Referencias:
Lugar: New York; Año: 2010 vol. 17 p. 202 - 209
ISSN:
1072-0502
Resumen:
The modulation of memory processes is one of the several functions of the endocannabinoid system (ECS) in the brain, with
CB1 receptors highly expressed in areas such as the dorsal hippocampus. Experimental evidence suggested an important
role of the ECS in aversively motivated memories. Similarly, glucocorticoids released in response to stress exposure also
modulates memory formation, and both stress and dexamethasone activate the ECS. Here, we investigate the interaction
between the ECS and glucocorticoids in the hippocampus in the modulation of fear memory consolidation. Two protocols
with different shock intensities were used in order to control the level of aversiveness. Local infusion of AM251 into the
hippocampus immediately after training was amnestic in the strong, but not in the weak protocol. Moreover, AM251
was amnestic in animals stressed 0, but not 30-min prior to the weak protocol, reverting the stress-induced facilitatory
effect. Finally, intrahippocampal AM251 infusion reduced memory in animals that received dexamethasone immediately,
but not 30 min before training. These results are (1) consistent with the view that the dorsal hippocampus ECS is activated
on demand, in a rapid and short-lived fashion in order to modulate the consolidation of an aversive memory, and (2)
show that this recruitment seems to be mediated by glucocorticoids, either in the hippocampus or in other brain
regions functionally associated with the hippocampus